That's very interesting. I remember when quads first came out a few years ago, I had this discussion with a friend of mine. He was saying that I had to try a quad because they were faster. I told him dude, that's impossible, there is literally an extra fin. Extra fin equals more drag quals slower. Anyway, a few years later, and I finally did try a quad and... yes, they are faster.
Maybe its because of how we surf a quad, we're going more down the line and not top to bottom, so maybe it just feels faster. Or... maybe its got to do with those vortices, where the back fin doesn't experience as much drag because its hiding behind the front fin and just channeling all the water down the center of the board.
But, yeah, I reckon most surfers would agree, quads are faster.
That's a good point on the perception of speed, I bet that you're right on that. I love my keel-finned fish and feel like it flies, but mostly in a straight line.
For most quad setups, that vortex that hits the trailing fin will occur at such a sharp angle of attach that the increase in drag from the front fin would most definitely be bigger than the savings of the back one going through turbulent water. I hear it around the breaks too that the quads are faster, but I'd argue that they just lead to that more linear surfing style where the board really "grips" the water because of the increased lift.
Quads are way faster in the surf. This past winter while in Hawaii I had a board made with five boxes. I took it out as a thruster the first couple days - worked great. Next, I surfed it as a quad - worked better. Same spot with same sized waves (a little overhead). As a quad it was much faster. I could make it around sections that I could not when it was set up as a thruster. I then had a singe fin longboard modified to add four boxes. When I rode that as a quad I had the same experience. I believe the conventional thinking is that when a thruster and quad are on the rail they both have two fins in the wave, but the thruster trailing fin slows the board down due to its position in the center of the board. Same with a single fin, the large center fin in the middle of the board slows it down. While not impossible, I think it is very difficult to replicate this in the lab how a board works in the surf.
That's very interesting. I remember when quads first came out a few years ago, I had this discussion with a friend of mine. He was saying that I had to try a quad because they were faster. I told him dude, that's impossible, there is literally an extra fin. Extra fin equals more drag quals slower. Anyway, a few years later, and I finally did try a quad and... yes, they are faster.
Maybe its because of how we surf a quad, we're going more down the line and not top to bottom, so maybe it just feels faster. Or... maybe its got to do with those vortices, where the back fin doesn't experience as much drag because its hiding behind the front fin and just channeling all the water down the center of the board.
But, yeah, I reckon most surfers would agree, quads are faster.
That's a good point on the perception of speed, I bet that you're right on that. I love my keel-finned fish and feel like it flies, but mostly in a straight line.
For most quad setups, that vortex that hits the trailing fin will occur at such a sharp angle of attach that the increase in drag from the front fin would most definitely be bigger than the savings of the back one going through turbulent water. I hear it around the breaks too that the quads are faster, but I'd argue that they just lead to that more linear surfing style where the board really "grips" the water because of the increased lift.
Appreciate the comments as always, Rian!
Quads are way faster in the surf. This past winter while in Hawaii I had a board made with five boxes. I took it out as a thruster the first couple days - worked great. Next, I surfed it as a quad - worked better. Same spot with same sized waves (a little overhead). As a quad it was much faster. I could make it around sections that I could not when it was set up as a thruster. I then had a singe fin longboard modified to add four boxes. When I rode that as a quad I had the same experience. I believe the conventional thinking is that when a thruster and quad are on the rail they both have two fins in the wave, but the thruster trailing fin slows the board down due to its position in the center of the board. Same with a single fin, the large center fin in the middle of the board slows it down. While not impossible, I think it is very difficult to replicate this in the lab how a board works in the surf.
Also, thx for your great Substack.